The present invention relates to a system for assisting in regenerating depollution means integrated in an exhaust system of an engine for a motor vehicle.
For example, it is known that such depollution means may include a NOx trap, i.e. a system for reducing polluting emissions from motor vehicle engines.
The engine is then associated with means for monitoring its operation to cause its operation to switch between standard operation in lean mode and regenerating operation in rich mode, depending on various parameters for monitoring the operation of the engine.
In standard operation in lean mode, the NOx trap stocks NOx, and once the trap becomes saturated, trap regeneration is triggered by switching the engine to operate in a rich mode of operation for destocking purposes, during which the engine produces reducing agents such as CO and HC, for example.
This is performed in conventional manner by modifying at least one parameter for controlling the operation of the engine, i.e. at least one parameter relating to the injection of fuel into the engine (quantity, phase position, pressure, etc. . . . ) and/or at least one parameter in the air feed loop of the engine (air flow rate, recycling, turbocompressor pressure, etc. . . . ).
The various adjustments of these parameters enable predetermined objectives to be reached in terms of delivered torque, pollution emissions, noise, etc. . . . .
Unfortunately, in this mode of operation, it is necessary to find a compromise between regenerating the NOx trap and oxidizing the reducing agents HC and CO as completely as possible.